The Biostatistics Core will provide the personnel and knowledge for the maximum utilization of the data collected by the investigators in the Oral Cancer Research Program Project (OCRPP). Statistical issues will be addressed at every level of investigation; from the design of experiments, to the maintenance of data quality, to the description and inferential statements made from the collected data. The specific aims of the Biostatistics Core are then: . To collaborate with all OCRPP investigators in protocol design and modification, . To develop and implement a program of data quality control, . To assist in developing and implementing databases for individual laboratories and to plan and implement shared databases, . To conduct statistical analyses of the data generated by OCRPP supported studies in close collaboration with project investigators, . To ensure that new methodologies are developed when needed to serve the work of the program project, and . To ensure that statistical issues are addressed in key program decisions. The Biostatistics Core will be directed by Dr. Dennis Pearl who will have overall responsibility for the activities of the core. Dr. Pearl is a Professor of statistics and Biostatistics with more than 15 years of experience collaborating in cancer related research. He is also the Associate Director for Design and Analysis of The Ohio State University's Biostatistics Program located in the medical center. Staff from the Biostatistics program, under Dr. Pearl's supervision, will perform much of the computational aspects of the OCRPP Biostatistics Core (e.g. working with each laboratory on data quality issues, preparing data sets for analyses and assisting Dr. Pearl in statistical programming tasks related to the analyses of data).